41.5.2 Clocks

The GMAC peripheral relies on a system clock from the Main Clock Controller (MCLK) for register access and GMAC MCK.

In MII mode, the actual Transmit or Reference Clock (GTXCK) and Receive Clock (GRXCK) are external signals.

In RMII mode, the actual Reference Clock (REF_CLK) is an external signal.

The respective pins are configured in the PORT peripheral.